Traffic and environmental impacts of constructing and operating a BRT service: Case study in Amman, Jordan

Abstract Road authorities are committed to improving community infrastructure through Bus Rapid Transit (BRT) projects. Yet, these initiatives often disrupt traffic, as seen in the Amman BRT project. A study assessed traffic conditions during various stages to address these disruptions, including simulated BRT operations. The research collected data on traffic volume, travel time, delays, and transit ridership before, during, and after construction and after BRT operations began. As a case study, the study focused on the impact of Amman’s first mass transit system at the Yajouz intersection. Traffic volumes decreased by 28% during construction, reducing delays significantly from 118.03 to 91.04 seconds. Although average speeds increased slightly (one km/h, on average), travel time doubled, negatively impacting 84% of businesses due to considering alternative routes for traveller destinations. However, delays significantly reduced after construction to 58 seconds per vehicle despite the higher traffic volume. Traffic simulations during construction underestimated observed delays (53.5 seconds per vehicle vs. 73.7 seconds per vehicle), still indicating a Level of Service (LOS) E. In BRT operation, modelled delays (55.8 seconds per vehicle) were lower than observed (63.8 seconds per vehicle), maintaining same LOS level. BRT minimally impacted ridership, an expected outcome given its trial phase. Environmental assessments revealed emissions peaking during construction, with a 25% modal shift to BRT yielding the lowest emissions. The study stresses sustainable urban mobility, advocating for meticulous planning, adaptable policies, and public awareness, emphasizing the need for detailed pedestrian research in this context.